O'nyong'nyong virus

The O'nyong - nyong fever is a viral infection and is caused by the same virus. The RNA virus belonging to the genus Alphavirus, family togaviruses. There is a relationship to the Chikungunya virus. The name means " joint breaking".

Occurrence

East and Central Africa. The virus has been found in Kenya, Malawi, Mozambique, Tanzania, Uganda, Senegal and the Central African Republic. Also tourist areas are affected. The disease occurs sporadically as an epidemic. Between the epidemics can often be 10 to 20 years, while the infection rate in the population to 80 %. The virus was first identified during a large epidemic between 1959 and 1962 in Uganda. At that time affected two million people. It is an extra- human reservoir suspected.

Transmission

O'nyong - Nyong is a Arbovirusinfektion. Transmission is by mosquitoes ( Anopheles gambiae and Anopheles funestus ). The mosquitoes are crepuscular, their distribution is linked to the presence of standing water.

Diagnosis

Typical travel history, detection of antibodies in the blood, Clinical picture. Confusion with chikungunya are possible.

Disease course and symptoms

The incubation period is 8-11 days. The disease begins suddenly with chills and high fever, headache, and lymphadenitis. There is leukopenia with relative lymphocytosis. Characteristic symptoms are severe, symmetrical joint pain ( polyarthralgia ), which may consist of several weeks. Below maculopapular rash in about 60 % of cases. Enantheme the cheek and palate mucosa may occur. The symptoms resolve after two weeks. Inapparent infections ( without malaise) are common. There remains a long-lasting immunity. Deadly curves are not known.

Therapy

A causal therapy or vaccination does not exist, the treatment is symptomatic.

Prevention

Consistent protection from mosquito bites: Repellents, mosquito nets, bright, long clothing, avoiding outdoor stays during and after dusk.